-A INPUT -m state --state NEW -m tcp -p tcp --dport 20000:25000 -j ACCEPT
-A INPUT -m state --state NEW -m tcp -p tcp --dport 20004 -j ACCEPT
Those are my two rules I made in my iptables in an attempt to open up all the ports from 20000:25000 when I realized the first didn't work I tried just an individual port, but still not open, the ports are being used for Minecraft and so with iptables on I can't connect to the servers, with them off, I can connect to the Minecraft servers no problem.
Yes I have been restarting my iptables each time and I'm on CentOS.